The hypothesis of the study is that LY303366, a new echincandin, in both a high (70 mg on day 1, 35 mg on days 2-21) and low (50 mg on day 1, 25 mg on days 2-21) IV dosage regimen will be efficacious and safe for the treatment of patients with esophageal candidiasis. The primary objective is to evaluate the safety and efficacy of two intravenous dosage regimens of LY303366 in the treatment of patients with esophageal candidiasis. The secondary objectives are as follows: to evaluate the mycologic response of 2 regimens of LY303366 against Candida species at end of therapy; to identify dosages regimens of LY303366 which may be efficacious in future clinical trials in patients with candidiasis; to determine pharmacokinetics of LY303366, and attempt to correlate pharmacokinetic data with efficacy and safety parameters. LY303366 is a semi-synthetic derivative of a natural product class of antifungal agents called echinocandins. The cyclic lipopeptides are noncompetitive inhibitors of (1,3)-B-D-glucan synthase which produces glucan polymers, a vital component of the fungal cell wall. The spectrum of activity of LY303366 includes Candida (all species), Aspergillus, and Pneumocystis. Mucocutaneous candidiasis is frequently observed in immunocompromised patients. This study would provide an agent that can be used when patients are resistant or intolerant to the currently available antifungals. This study will treat patients with esophageal candidiasis for 14 to 21 days, comparing 2 dosage regimens of LY303366. Doses were chosen based on plasma pharmacokinetic profiles documented in the Phase I studies and correlation with stringent animal models of infection.